Variable condenser



Feb. 16,1926. 1,572,897

. R,- E. MARBURY VARIABLE CONDENSER Filed Dec. 14, 1920 WITNESSES: INVENTOR fag/WWW Bd40fi 15: Pia/"bury fmAjW y BY ATTORNEY Patented Feb. 16, 1926.

UNITED STATES PATENT OFFICE. I

RALPH EL MARBURY, OF EDGEVJOOD IPAEK, PENNSYLVANIA, ASSIGNOR TO TESTING- HOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYL- VANIA.

VARIABLE Application filed December To all whom it may concern:

Be it known that I, RALPH E. biennium, a citizen of the United States, and a resident ofl ldgewood Park, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Variable Condensers, of which the following a specification.

This invention relates to condensers. more especially to variable condensers wherein the capacitance may be regulated at will. Such condensers are particularly adapted for use in wireless-transmission apparatus.

The present invention consists in a modification of the method and structure described and claimed in my copending application, Serial No; 426,969, filed Nov. 29, 1920, for air condensers and method of assembly.

The aforesaid application describes the making of air condensers by assembling a number of plates having alined openings therein on metal spacers or in jigs, passing metal rods through the alined openings in the plates and dipping the assembly in molten solder, whereby a unitary structure is formed. The stationary set of plates is formed with supports at three points and is, therefore, comparatively rigid. The movable set of plates, or rotor, has but a single support on one side thereof and is subject to distortion when force is accidentally applied to the opposite edges of such plates.

The present invention is designed to obviate this difficulty, it being among the objects thereof to provide a structure and a method of assembling the plates of a condenser of the type above set forth which shall render the entire structure more rigid and less expensive to manufacture.

In practicing my invention, I assemble a suitable number of plates alternating with corrugated'or crimped washers, and pass a rod or tube through the openings of the assembled plates and washers, and secure the same in position.

More specifically, I provide corrugated washers, the thickness of which is slightly greater than the spaces between the plates in the completed condenser. The washers and plates are assembled and the tube passed therethrough, and a sufiicient pressure is applied to the end plates to crush or fold the assembly to the desired thickness.

COIIDENSEE.

14., 1.929. Serial N0. 430,619.

Since the corrugated washers have very little strength, they readily bend, allowing the plates to assume the correct final position without the use of jigs or spacers. The assembly then dipped in solder, and, since the surface of the washers is comparatively large, there is a large number of points of contact between the washers and the plates into which the solder flows to form a very rigid unitary structure. Since each plate is supported at a plurality of points at a considerable distance from the central post or tube. the tendency for the plates to bend or twist out of parallel relation is minimized.

In the accompanying drawing forming a part hereof and illustrating a specific embodiment of my invention,

Fig. l is an elevational view of a completed condenser constructed in accordance with my invention;

Fig. 2 is a plan view of the movable plate portion or rotor,

Fig. 3 is an elevational view of the same;

Fig. 4- is a plan view of one of the washers utilized in my structure, and

Fig. 5 is an elevational view of the same.

The condenser 1 is formed with upper and lower frame members or plates 2 and 3 of non-conducting material, and a number of spaced supporting posts and 5 are secured therein by suitable means, here shown as threaded ends and nuts. Stationary plates 6 are assembled upon the posts t and 5 in any desired manner but preferably by placing a suitable number of such plates in a jig, with openings in alinement, passing posts 4 and 5 through such alined openings and dipping the assembly in molten solder. The stationary part of the condenser so formed is then fixed into the frame of the condenser.

The movable member or rotor 7 of the condenser is formed of a series of plates 8 of suitable shape, preferably sector of a circle, as a semi-circle, having projecting port-ions with central openings 9 formed therein. Corrugated washers 10, having openings 11 therein, are assembled alternately with plates 8, the openings 11 and 9 being in alinement. A tube or post 12 is passed through the assembled structure, and pressure is applied to the upper and lower plates to crimp or compress the structure to the desired shape, giving the correct spacing between adjacent plates 8. A rod 13 passed through plates 2 and 3 and throu 'h tube 12, said tube being secured to rod i3; by set screw 14 or any other suitable means. The rod is then loo ed into position on the frame by any suitable means, such as .locl:- nuts 15. A handle 16 of any suitable 'ype is secured to therod 13 to allow ready manipulation of the rotor.

My improved construction is Qonipaia tively inexpensive to manuuicture and does not require specially skilled operators. Although I have described the assembling of the rotor by stacking alternately 8 and washers l0 and then passing tube 12 tlierethrough and soldering the same together, it is obvious that deta'ls of manipulation may be varied at will. For instance, I may first provide the tube or post- 12 and assemble the plates and washers reen. crimp the same to the final form,v and then secure the parts together in any manner, as by soldering, wedging or welding.

It is also apparent that various changes in details of the structure of n condenser may be made without depa from the principles thereof. For instance, the corrugated Washers may be of any able form, the posts 4 and 5 may be mounted in any other manner, and the rotor 7 may be held in the structure by means other than that described above. I may apply the enser comprising spaced plates l openings. corrugated washers -l bc" .veen said. plates, a tube eX- 1 said openings and holding i ieir re ative positions, and a i pivotei A condenser eon'iprising spaced plates, resilient vva, s interposed between said plat-es and haw alined openings and a post extending; tn..ough sa d openings and s in their relative posi- ;hers under compression.

comprising spaced plane of still material and corruholding: said tiens with suit plates, said s1 acers covering only all part ot the surtace area of said roomy whereof. I have hereunto my name this th day 0t 1020.

RALPH E. MARBURY. 

